Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?s)Token\sType:.*?Client\sIP:\s+(?|(?<adfs_src>:x(?:\.x){3})|x(?:\.x){3},\K(?<adfs_src>x(?:\.x){3}))" test_str = ("Microsoft ADFS logs and here is an example: 05/07/2019 03:06:54 PM LogName=Security SourceName=AD FS Auditing EventCode=411 EventType=0 Type=Information ComputerName=x.y.z User=abc Sid=A-9-3-98-1231231313-1231231313-1231231313-406293 SidType=1 TaskCategory=Printers OpCode=Info RecordNumber=###### Keywords=Audit Failure, Classic Message=Token validation failed. See inner exception for more details. Additional Data Activity ID: 00000000-0000-0000-0000-000000000000 Token Type: http://schemas.microsoft.com/ws/2006/05/identitymodel/tokens/UserName Client IP: x.x.x.x,x.x.x.x Error message: user@foo.com -The user name or password is incorrect Exception details: System.IdentityModel.Tokens.SecurityTokenValidationException: user@foo.com ---> System.ComponentModel.Win32Exception: The user name or password is incorrect at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserHandle(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, SafeCloseHandle& tokenHandle, SafeLsaReturnBufferHandle& profileHandle) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserInfo(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String authenticationType, String issuerName) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUser(UserNameSecurityToken token, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String issuerName) at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateTokenInternal(SecurityToken token) --- End of inner exception stack trace --- at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateTokenInternal(SecurityToken token) at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateToken(SecurityToken token) System.ComponentModel.Win32Exception (0x80004005): The user name or password is incorrect at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserHandle(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, SafeCloseHandle& tokenHandle, SafeLsaReturnBufferHandle& profileHandle) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserInfo(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String authenticationType, String issuerName) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUser(UserNameSecurityToken token, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String issuerName) at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateTokenInternal(SecurityToken token)\n\n" "Looking for a regex that works when either one or more IPs are listed for Client IP\n\n" "Thx\n") matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html